US9034403B2 - Yeast extract containing γ-Glu-X or γ-Glu-X-Gly and a method for producing the same - Google Patents

Yeast extract containing γ-Glu-X or γ-Glu-X-Gly and a method for producing the same Download PDF

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US9034403B2
US9034403B2 US13/593,974 US201213593974A US9034403B2 US 9034403 B2 US9034403 B2 US 9034403B2 US 201213593974 A US201213593974 A US 201213593974A US 9034403 B2 US9034403 B2 US 9034403B2
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glu
gly
yeast
val
strain
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US20130045305A1 (en
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Hiroaki Nishiuchi
Wataru HOSHINO
Junko Yamazaki
Toshimi Mizukoshi
Vsevolod Aleksandovich Serebryanyy
Olga Aleksandrovna Sofyanovich
Dmitriy Aleksandrovich Cheshev
V. Elena Matrosova
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Ajinomoto Co Inc
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Ajinomoto Co Inc
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    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
    • C12P21/00—Preparation of peptides or proteins
    • C12P21/02—Preparation of peptides or proteins having a known sequence of two or more amino acids, e.g. glutathione
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K14/00—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
    • C07K14/37—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from fungi
    • C07K14/39—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from fungi from yeasts
    • C07K14/395—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from fungi from yeasts from Saccharomyces
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N1/00—Microorganisms; Compositions thereof; Processes of propagating, maintaining or preserving microorganisms or compositions thereof; Processes of preparing or isolating a composition containing a microorganism; Culture media therefor
    • C12N1/14—Fungi; Culture media therefor
    • C12N1/16—Yeasts; Culture media therefor
    • C12N1/18—Baker's yeast; Brewer's yeast

Definitions

  • the present invention relates to a yeast extract containing ⁇ -Glu-X-Gly or ⁇ -Glu-X and a method for producing the same.
  • the yeast extract of the present invention is useful in the field of foodstuffs such as seasonings and health foods.
  • Yeast extracts have a function of imparting atsumi (thickness), umami, etc. to foodstuffs, and have been widely used as seasonings in the field of foodstuffs.
  • glutathione (henceforth also referred to as “GSH”), which is a tripeptide consisting of glutamic acid, cysteine and glycine, is known to impart kokumi to foodstuffs (Ueda et al., Agric. Biol. Chem., 54, 163-169 (1990), Ueda et al., Biosci. Biotechnolo. Biochem., 61, 1977-1980 (1997)), and seasonings containing GSH have been developed.
  • CaSR calcium sensing receptor
  • esters including S- or O-carboxyalkylated ⁇ -glutamyl or ⁇ -asparagyl peptides etc.
  • kokumi substances are also reported as kokumi substances (WO2007/042288).
  • these peptides impart kokumi to foodstuffs like GSH, they do not have a reduced SH group unlike GSH.
  • a substance having the reduced SH group such as GSH is generally unstable, and titer thereof is reduced with formation of disulfide bond (WO2007/042288).
  • ⁇ -Glu-X, ⁇ -Glu-X-Gly etc. are considered useful from the viewpoint that the kokumi-imparting peptides not having the reduced SH group are stable.
  • glutathione which is one of the ⁇ -glutamyl compounds
  • ⁇ -glutamyl transpeptidase is known to transfer the glutamate of GSH at the ⁇ -position to another compound having an amino group, resulting in decomposition of GSH to cysteinylglycine (Protein Nucleic acid Enzyme, 1988-7, VOL. 33, NO. 9, ISSN 003909450, Special Issue “Epoch of glutathione research”, pp. 1432-1433).
  • Findings about the dipeptide ⁇ -Glu-X that have been reported include an analysis of the fermentation broth of Micrococcus glutamicus (Ronald et al., Journal of Biological Chemistry, 240, p 2508-2511 (1965)). This reference reported that the fermentation broth was loaded onto various columns to separate peptides etc., and to isolate ⁇ -Glu-Glu, ⁇ -Glu-Val, and ⁇ -Glu-Leu. However, these were found as a result of separation with various columns, and the amounts of these peptides contained in the broth were not determined.
  • GSH is usually biosynthesized by two different enzymes called ⁇ -glutamylcysteine synthetase, which combines Glu and Cys to generate ⁇ -Glu-Cys, and glutathione synthetase, which combines the produced ⁇ -Glu-Cys and Gly to generate GSH.
  • the aforementioned two kinds of microorganisms have a unique enzyme which is essentially a fusion of ⁇ -glutamylcysteine synthetase and glutathione synthetase. It was reported that, according to an in vitro analysis, the substrate recognition of this enzyme was slightly ambiguous, i.e., it also recognized amino acids other than Cys, and as a result, it could generate ⁇ -Glu-X and ⁇ -Glu-X-Gly. However, these are nevertheless in vitro results, and it was not described whether or not those microorganisms that produced marked amounts of peptides such as ⁇ -Glu-X and ⁇ -Glu-X-Gly, also contain many compounds having an amino group besides the target X.
  • Yeast extracts are seasonings which have been widely used in the field of foodstuffs, and are highly accepted by consumers. Therefore, a yeast extract can be used as a carrier of ⁇ -Glu-X-Gly or ⁇ -Glu-X. Yeast strains containing minerals have been studied for this use. It is known that if a metal is added to a medium, yeasts take up the metal into the cells (B. Volesky, H. A., Appl. Microbiol. Biotechnol., 42; 797-806 (1995)).
  • yeasts can be used to supply such trace elements via enrichment in foodstuffs (Japanese Patent Laid-open (Kokai) No. 2004-298014).
  • methods for producing mineral-containing yeast have been developed (Japanese Patent Laid-open No. 54-157890, Japanese Patent Laid-open No. 60-75279, Japanese Patent Publication (Kokoku) No. 6-16702).
  • mineral-containing yeast also have an advantage concerning taste.
  • yeast containing a high amount of magnesium are described in Japanese Patent Laid-open No. 8-332081.
  • This reference describes that although magnesium-enriched foodstuffs containing inorganic magnesium salt were also marketed, a strong bitterness and astringency was noted due to the mineral salt. As a result, it was quite more difficult to routinely eat the magnesium-enriched foodstuffs containing inorganic magnesium salt as compared to foodstuffs containing naturally occurring magnesium.
  • Japanese Patent Laid-open No. 8-332081 also discloses a technique of producing a natural material by making yeast take up magnesium. As for nutritional merit, the technique disclosed in Japanese Patent Laid-open No. 2008-99578 can be exemplified.
  • yeast take up a target substance and adding either the yeast or a yeast extract to foodstuffs, as compared to simply adding the target substance to foodstuffs.
  • unlike minerals, which are essential nutrients the ability of yeast to take up an amino acid or a peptide is delicately controlled, and it simply applying the technique for incorporating minerals into yeast to the techniques for uptake of amino acid or peptides was considered to be difficult.
  • Hgt1p Although GSH and the dimer thereof, GSSG, were taken into cells by Hgt1p, uptake of GSH by Hgt1p was not affected even in the presence of excessive amounts of amino acids, various dipeptides, and tripeptides. Therefore, it is considered that Hgt1p is not a nonspecific transporter as once thought, but a transporter specific to GSH (Bourbouloux et al., Journal of Biological Chemistry, 275, pp. 13259-13265 (2000)). Furthermore, a search for the active site of Hgt1p has also been performed (Kaur et al., FEMS Yeast Res., 9, 849-866 (2009)).
  • aspects of the present invention include providing a yeast extract containing ⁇ -Glu-X or ⁇ -Glu-X-Gly, and providing a method for producing the yeast.
  • a yeast took up ⁇ -Glu-X and ⁇ -Glu-X-Gly (X represents an amino acid or an amino acid derivative other than Cys, the same shall apply in the following descriptions) into cells, and a yeast extract containing ⁇ -Glu-X or ⁇ -Glu-X-Gly could be produced by preparing the yeast extract from a yeast cultured in a medium containing ⁇ -Glu-X or ⁇ -Glu-X-Gly. Moreover, it was found that if yeast was cultured in a medium containing ⁇ -Glu-X or X-Gly, these compounds were taken up into the cells, and ⁇ -Glu-X-Gly could be generated via an intracellular enzymatic reaction.
  • a yeast extract containing ⁇ -Glu-X or ⁇ -Glu-X-Gly could be produced by allowing ⁇ -glutamyl transferase to act on a yeast extract raw material to which an amino acid or a peptide selected from X and X-Gly was added.
  • yeast extract as described above, which contains the peptide in a total amount of 0.02% or more.
  • yeast extract as described above, wherein the yeast is Saccharomyces cerevisiae.
  • the medium contains 0.1 ppm or more of the peptide
  • the yeast extract contains the peptide selected from the group consisting of ⁇ -Glu-X and ⁇ -Glu-X-Gly in a total amount of 0.005% or more based on dry weight of the yeast extract.
  • yeast is Saccharomyces cerevisiae.
  • yeast is Saccharomyces cerevisiae.
  • a yeast extract containing ⁇ -Glu-X, ⁇ -Glu-X-Gly, or these both can be produced.
  • a yeast extract containing these peptides is excellent in kokumi.
  • yeast extract containing ⁇ -Glu-X is also useful as a raw material for producing a yeast extract containing ⁇ -Glu-X-Gly.
  • FIG. 1 shows HPLC-MS chromatograms of ⁇ -Glu-Val-Gly, ⁇ -Glu-Val and Val-Gly standard samples.
  • FIG. 2 shows HPLC-MS chromatograms of ⁇ -Glu-Val-Gly, ⁇ -Glu-Val, Val-Gly, ⁇ -Glu-nVal-Gly, and ⁇ -Glu-nVal standard samples.
  • FIG. 3 shows the structure of the plasmid pUC19AOX-G418-BRI.
  • FIG. 4 shows the structure of the plasmid pKS-URA3-13.
  • FIG. 5 shows construction of the plasmid pKS-URA3-13-kanMX.
  • FIG. 6 shows construction of the plasmid pLoxP-PADH1-kanR5.
  • FIG. 7 shows construction of the plasmid pKS-URA3-PADH1-LR.
  • FIG. 8 shows construction of the plasmid pKS-URA3-P-ADH1.
  • FIG. 9 shows preparation of a DNA fragment used for promoter substitution.
  • CDS coding sequence of target gene
  • up-CDS region upstream target gene.
  • Horizontally stroked boxes designate a 40-base pairs overlapping region
  • black box designates a 40-base fragment for homologous recombination with 5′-region of target gene.
  • FIG. 10 shows the map of pUG6-PTDH3.
  • FIG. 11 shows cloning of the P TDH3 -GSH2 cassette into multicopy yeast vector.
  • the yeast extract in accordance with the presently described subject matter contains a peptide such as ⁇ -Glu-X and ⁇ -Glu-X-Gly in a total amount of 0.005% or more based on dry weight of the yeast extract, wherein X can represent an amino acid or an amino acid derivative other than Cys and derivatives thereof.
  • the yeast extract can contain the peptide in a total amount of 0.005% or more, 0.02% or more, 0.1% or more, or 0.5% or more, based on dry weight of the yeast extract.
  • the yeast used as the raw material of the yeast extract is the same as the yeast used for the method described later.
  • Glu and Gly in the peptide represent glutamic acid and glycine, respectively.
  • the symbol “-” represents a peptide bond.
  • “ ⁇ ” of ⁇ -Glu means that another amino acid binds via the carboxy group of the glutamic acid at the ⁇ -position.
  • X can represent any of 19 kinds of amino acid among the natural amino acids or a derivative thereof, except for Cys and derivatives thereof. Cys represents cysteine, and examples of the derivatives thereof include ⁇ -aminobutyric acid, ⁇ -aminobutyric acid, and so forth.
  • the aforementioned amino acids except for Cys and derivatives thereof include neutral amino acids such as glycine (Gly), alanine (Ala), valine (Val), leucine (Leu), isoleucine (Ile), serine (Ser), threonine (Thr), methionine (Met), asparagine (Asn), glutamine (Gln) and proline (Pro), acidic amino acids such as aspartic acid (Asp) and glutamic acid (Glu), basic amino acids such as lysine (Lys), arginine (Arg) and histidine (His), and aromatic amino acids such as phenylalanine (Phe), tyrosine (Tyr) and tryptophan (Trp).
  • neutral amino acids such as glycine (Gly), alanine (Ala), valine (Val), leucine (Leu), isoleucine (Ile), serine (Ser), threonine (Thr), methionine (Met), as
  • X is a hydrophobic amino acid
  • the kokumi effect of the peptide is high, and such a peptide is a particular example.
  • hydrophobic amino acids include Val, Ala, Leu, Phe, and so forth.
  • Examples of the derivatives of amino acid include, for example, norvaline (nVal), norleucine (nLeu), tert-leucine (tLeu), hydroxyproline (Hyp), and so forth.
  • peptides particular examples are ⁇ -Glu-Val-Gly, ⁇ -Glu-Val, ⁇ -Glu-nVal-Gly, ⁇ -Glu-nVal, and Val-Gly.
  • amino acids and amino acid derivatives are all L-isomers.
  • the form of the yeast extract is not particularly limited, and it may be in the form of powder or solution.
  • the yeast extract can have the same uses as that of conventional yeast extracts, for example, seasonings, food additives, health foods, and so forth.
  • the yeast extract is excellent in its kokumi-imparting effect.
  • Kokumi means a taste that cannot be expressed with the five basic tastes, and means a taste that enhances not only the basic tastes but also marginal tastes of the basic tastes, such as thickness, growth (mouthfulness), continuity, and harmony.
  • an umami substance such as sodium L-glutamate and taste nucleotides, and/or a salty substance such as sodium chloride may be added to the yeast extract.
  • an umami substance and/or a salty substance may be added to seasonings, food additives or health foods together with the yeast extract in accordance with the presently described subject matter.
  • yeast extracts containing ⁇ -Glu-Val-Gly especially a solution containing a yeast extract, produced by the method described herein, showed a higher kokumi-enhancing effect as compared to a ⁇ -Glu-Val-Gly solution having the same concentration of ⁇ -Glu-Val-Gly as that of the solution. This indicates the usefulness of the yeast extract.
  • yeast extract in accordance with the presently described subject matter can be produced by, for example, the methods of the present invention described herein.
  • the first method in accordance with the presently described subject matter is a method for producing a yeast extract containing a peptide selected from ⁇ -Glu-X-Gly and ⁇ -Glu-X, which includes the steps of culturing a yeast in a medium containing a peptide selected from ⁇ -Glu-X-Gly, ⁇ -Glu-X and X-Gly, and preparing a yeast extract from the obtained cells, wherein X represents an amino acid or an amino acid derivative other than Cys and derivatives thereof.
  • the yeast is not particularly limited, so long as the chosen yeast can take up ⁇ -Glu-X, ⁇ -Glu-X-Gly or X-Gly into the cells thereof.
  • yeasts belonging to the genus Saccharomyces such as Saccharomyces cerevisiae
  • those belonging to the genus Candida such as Candida utilis
  • those belonging to the genus Pichia such as Pichia pastoris
  • those belonging to the genus Schizosaccharomyces such as Schizosaccharomyces pombe .
  • Saccharomyces cerevisiae and Candida utilis are particular examples, and are frequently used for production of yeast extracts.
  • the yeast may be a monoploid, or may have diploidy or a further higher polyploidy.
  • the yeast may be any wild-type strain, or various mutant strains, so long as the chosen yeast can intracellularly take up ⁇ -Glu-X, ⁇ -Glu-X-Gly or X-Gly and accumulate ⁇ -Glu-X and/or ⁇ -Glu-X-Gly in the cells.
  • mutant strains include a strain with enhanced activities or activity of ⁇ -glutamylcysteine synthetase (GSH1) and/or glutathione synthetase (GSH2).
  • GSH1 ⁇ -glutamylcysteine synthetase
  • GSH2 glutathione synthetase
  • the yeast may also be modified so that the uptake of ⁇ -Glu-X, ⁇ -Glu-X-Gly or X-Gly into the cells is improved.
  • the uptake of ⁇ -Glu-X, ⁇ -Glu-X-Gly or X-Gly can be improved by enhancing an activity of a protein which participates in the uptake of these peptides.
  • Hgt1p had been reported to be a transporter specific to GSH, it is shown that, by enhancing the activity of Hgt1p, the uptake of ⁇ -Glu-Val-Gly or ⁇ -Glu-nVal-Gly can be improved (see the examples section). Therefore, it is possible that the uptake of not only ⁇ -Glu-Val-Gly, but also other ⁇ -Glu-X-Gly peptides into the cells can be improved by enhancing the Hgt1p activity.
  • Ptr2p had been reported to be an oligopeptide transporter. It is shown that, by enhancing the activity of Ptr2p, the uptake of Val-Gly seemed to be enhanced (see the examples section). Therefore, it is possible that the uptake of not only Val-Gly, but also other X-Gly peptides into the cells can be improved by enhancing Ptr2p activity.
  • the nucleotide sequence of the gene coding for Ptr2p of Saccharomyces cerevisiae is shown in SEQ ID NO: 58.
  • the amino acid sequence encoded by this nucleotide sequence is shown in SEQ ID NO: 59.
  • the methods for enhancing the activity of the aforementioned enzyme or protein include enhancing expression thereof by replacing the promoter of the gene coding for the enzyme or protein on the chromosome with a stronger promoter, enhancing expression thereof by inserting the target gene into the chromosome to introduce two or more copies thereof, and enhancing expression thereof by incorporating a plasmid containing the target gene into the yeast, or the like.
  • a highly active conventional promoter may be obtained by using various reporter genes, or a known high expression promoter such as PGK1, PDC1, TDH3, TEF1 and HXT7 may be used.
  • a plasmid having the replication origin of CEN4, or a multi-copy plasmid having the replication origin of 2 ⁇ m DNA may be used.
  • a transposon may be used in order to introduce a target gene into an arbitrary region of the chromosome, or the target gene may be introduced by using rDNA sequences as a target, which is present in a copy number of 150 in the cell.
  • Enhancement of the activity of ⁇ -glutamylcysteine synthetase is disclosed in, for example, U.S. Pat. No. 7,553,638; Otake Y. et al., Bioscience and Industry, volume 50, No. 10, pp. 989-994, 1992, and so forth.
  • disruption of the glutathione synthetase gene is disclosed in U.S. Pat. No. 7,553,638, the glutathione synthetase activity can be enhanced in the same manner as that for enhancement of the activity of ⁇ -glutamylcysteine synthetase.
  • the activity of Hgt1p can also be enhanced in a similar manner.
  • the nucleotide sequences of the genes coding for Gsh1p and Gsh2p of Saccharomyces cerevisiae are disclosed in Saccharomyces Genome Database (http://www.yeastgenome.org/).
  • the nucleotide sequences of the genes coding for Gsh1p and Gsh2p of Candida utilis are disclosed in U.S. Pat. No. 7,553,638.
  • the nucleotide sequence of the gene coding for Gsh1p of Saccharomyces cerevisiae is shown in SEQ ID NO: 60.
  • the amino acid sequence encoded by this nucleotide sequence is shown in SEQ ID NO: 61.
  • the nucleotide sequence of the gene coding for Gsh2p of Saccharomyces cerevisiae is shown in SEQ ID NO: 19.
  • the amino acid sequence encoded by this nucleotide sequence is shown in SEQ ID NO: 20.
  • Hgt1p The gene coding for Hgt1p can be obtained from Saccharomyces Genome Database (http://www.yeastgenome.org/). Synonyms of Hgt1p include Gsh11p, Opt1p or the like.
  • the sequence disclosed as GSH11 of Saccharomyces cerevisiae is shown in SEQ ID NO: 21.
  • amino acid sequence encoded by this nucleotide sequence is shown in SEQ ID NO: 22.
  • the method for producing the yeast extract is explained below.
  • a yeast is cultured in a medium containing the peptide.
  • the medium is not particularly limited, so long as a medium in which the yeast can proliferate is chosen, and is not limited to the SD medium described in the examples.
  • a medium usually used for industrial purposes can be used.
  • ⁇ -Glu-X, ⁇ -Glu-X-Gly or X-Gly is added to the aforementioned medium.
  • One type of these peptides may be added, or a arbitrary mixture of two or more kinds of these peptides may be added.
  • These peptides may be present in the medium from the start of the culture, or may be added to the medium at an arbitrary time during the culture.
  • the peptides can be added at 0 to 50 hours before the end of the culture (0 hour means that the culture is terminated immediately after the addition), 0.1 to 24 hours before the end of the culture, or 0.5 to 6 hours before the end of the culture.
  • the peptides are added during the culture, they may be continuously added.
  • a preculture Prior to the culture in the medium containing the peptides, a preculture may be performed.
  • the medium used for the preculture may or may not contain the peptides.
  • the peptides are added to the medium usually in an amount of 0.1 ppm or more, 0.5 ppm or more, 1 ppm or more, 10 ppm or more, or 50 ppm or more, in terms of the final concentration in the culture broth at the time of the addition.
  • the upper limit of the amount of the peptides is not particularly limited, it can be exemplified as less than 100,000 or 50,000 ppm from an aspect of production cost, it is usually 10,000 ppm or less, 1,000 ppm or less, or 500 ppm or less.
  • the peptide amount to be added to the medium is usually not less than 0.1 ppm, 0.5 ppm, 1 ppm, 10 ppm, or 50 ppm in terms of the final concentration in the culture broth at the time of the addition.
  • the upper limit of the peptide amount is not specifically limited. However, the upper limit of the peptide amount can be set, for example, to be not more than 100,000 ppm or not more than 50,000 ppm in view of the production cost.
  • the upper limit of the peptide amount is usually not more than 10,000 ppm, 1,000 ppm, or 500 ppm.
  • the same conditions as those used for usual production of yeast extracts can be used, and they may be suitably changed according to the chosen yeast.
  • Arbitrary methods such as batch culture, fed-batch culture, and continuous culture may be used.
  • the yeast is Saccharomyces cerevisiae , it is preferably aerobically cultured by shaking or the like at 25 to 35° C., 27 to 33° C., or 28 to 32° C.
  • ⁇ -Glu-X, ⁇ -Glu-X-Gly, or both can accumulate in the cells of the yeast.
  • ⁇ -Glu-X or X-Gly is added to the medium, these peptides accumulate in the cells, and in addition, ⁇ -Glu-X-Gly also accumulates. It is estimated that this is because ⁇ -Glu-X-Gly is produced from ⁇ -Glu-X and X-Gly, which have been taken up into the cells by the action of intracellular ⁇ -glutamyl transferase.
  • yeast extracts produced by the conventional methods do not contain ⁇ -Glu-X or ⁇ -Glu-X-Gly at a high concentration, even if they are produced from a yeast containing GSH at a high concentration.
  • the yeast extract can be prepared from the yeast in the same manner as that used for conventional production of yeast extracts.
  • the yeast extract may be obtained by subjecting the yeast cells to hot water extraction and processing the extract, or by digesting the yeast cells and processing the digestion product. Furthermore, the obtained yeast extract may be concentrated, or may be dried and thereby made into powdered form, if needed.
  • yeast extract in which the amount of ⁇ -Glu-X, ⁇ -Glu-X-Gly or both are increased is obtained.
  • the yeast extract can contain ⁇ -Glu-X, ⁇ -Glu-X-Gly, or both in a total amount of 0.005% or more, 0.02% or more, 0.1% or more, or 0.5% or more, based on dry weight of the yeast extract.
  • yeast extract containing ⁇ -Glu-X-Gly By allowing a ⁇ -glutamyl transferase to act on the yeast extract containing ⁇ -Glu-X obtained as described above in the same manner as that of the method described below, a yeast extract containing ⁇ -Glu-X-Gly can be produced.
  • the second method in accordance with the presently described subject matter is a method for producing a yeast extract containing a peptide selected from ⁇ -Glu-X and ⁇ -Glu-X-Gly, which includes the steps of allowing a ⁇ -glutamyl transferase to act on a yeast extract raw material to which an amino acid or a peptide such as X and X-Gly is added, wherein X represents an amino acid or an amino acid derivative other than Cys and derivatives thereof.
  • a yeast extract containing ⁇ -Glu-X or ⁇ -Glu-X-Gly can also be obtained by allowing a ⁇ -glutamyl transferase to act on a yeast extract containing X or X-Gly.
  • the yeast extract containing X and/or X-Gly may be prepared from a yeast cultured in a medium containing X and/or X-Gly, or may be obtained by adding X and/or X-Gly to a yeast extract raw material.
  • yeast extract raw material a yeast extract obtained by a conventional method can be used.
  • X or X-Gly may be added to the yeast extract raw material, or an arbitrary mixture of two or more kinds of them may be added.
  • X and/or X-Gly is added in a total amount of 1% or more, 5% or more, 10% or more, based on dry weight of the yeast extract raw material.
  • the reaction catalyzed by the ⁇ -glutamyl transferase is performed in an aqueous solvent such as water or buffers.
  • an aqueous solvent such as water or buffers.
  • the yeast extract raw material is dissolved in the aqueous solvent, and the ⁇ -glutamyl transferase is added.
  • the reaction conditions can be suitably determined according to the ⁇ -glutamyl transferase to be used.
  • the reaction is usually allowed at pH 3 to 9 and 15 to 70° C. for 1 to 300 minutes, or pH 5 to 8 and 30 to 70° C. for 5 to 150 minutes.
  • Concentration of the yeast extract raw material in the aqueous solvent may be determined in view of ease of handling.
  • the concentration is usually 0.1 to 50%, or 0.5 to 20%, in terms of dry weight of the yeast extract raw material.
  • ⁇ -glutamyl transferase examples include glutaminase, ⁇ -glutamyl transpeptidase ( ⁇ -GTP), and so forth.
  • amount of the enzyme in the case of ⁇ -GTP, it is usually 0.001 to 1000 units/ml, 0.005 to 100 units/ml, y 0.01 to 25 units/ml, or 0.05 to 10 units/ml, wherein 1 unit is defined to be the activity of liberating 1.0 mmole of p-nitroaniline from ⁇ -glutamyl-p-nitroanilide per 1 minute in a solution at pH 8.5 and 25° C. (definition described in Sigma General Catalogue, 2008-2009 Edition, p. 917).
  • the amount of glutaminase can also be determined in a manner similar to that for ⁇ -GTP.
  • the ⁇ -glutamyl transferase may be inactivated by, for example, a heat treatment at 80 to 100° C., but this is not always necessary.
  • a ⁇ -glutamyl compound for example, GSH
  • GSH contained in the yeast extract may also be used as a substrate.
  • a yeast extract prepared from yeast in which the content of GSH is increased for example, a yeast in which activities or activity of Gsh1p and/or Gsh2p is enhanced can be used.
  • a greater GSH content in the yeast extract is preferred, it is usually 1 to 50%, 1 to 30%, or 5 to 20%, based on dry weight of the yeast extract.
  • yeast extract in which the amount of ⁇ -Glu-X, ⁇ -Glu-X-Gly, or both is increased is obtained.
  • the yeast extract can contain ⁇ -Glu-X, ⁇ -Glu-X-Gly or both in a total amount of 0.005% or more, 0.02% or more, 0.1% or more, or 0.5% or more, based on dry weight of the yeast extract.
  • the obtained yeast extract may be concentrated, or may be dried and thereby made into powdered form, if needed.
  • ⁇ -Glu-Val-Gly, ⁇ -Glu-Val, and Val-Gly contents in various commercially available yeast extracts were measured by fluorescence derivatization of the peptides with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC), and detection by LC-MS/MS according to the method described below.
  • AQC 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate
  • an AQC reagent solution prepared by dissolving the reagent powder of the aforementioned reagent kit in 1 mL of acetonitrile
  • This mixture was heated at 55° C. for 10 minutes, and then 100 ⁇ L of 0.1% formic acid aqueous solution was added to the mixture to prepare a sample for analysis.
  • the sample for analysis prepared as described above was subjected to separation by the reverse phase liquid chromatography described below, and then introduced into a mass spectrometer.
  • the separation conditions are as follows.
  • Elution conditions elution was performed by using mixtures of the mobile phase A and the mobile phase B.
  • the ratios of the mobile phase B to the mixtures are as follows: 0 minute (5%), 0 to 17 minutes (5 to 40%), 17 to 17.1 minutes (40 to 80%), 17.1 to 19 minutes (80%), 19 to 19.1 minutes (80 to 5%), 19.1 to 27 minutes (5%).
  • the derivatized compounds of ⁇ -Glu-Val-Gly, ⁇ -Glu-Val, and Val-Gly were quantified by using analysis software, Analyst ver. 1.4.2 (AB Sciex).
  • As the internal standard substance for performing the quantification derivatized compounds of Ala-d3 were used in the case of ⁇ -Glu-Val-Gly and ⁇ -Glu-Val, and a derivatized compound of Val-d8 was used in the case of Val-Gly, respectively.
  • the results are shown in Table 2. In the table, “ND” means that the amount was below quantitation limit (the same shall apply to the following).
  • the analysis results (HPLC-MS chromatograms) of derivatized internal standard amino acids, ⁇ -Glu-Val-Gly, ⁇ -Glu-Val, and Val-Gly standard samples are shown in FIG. 1 .
  • the amount of ⁇ -Glu-Val-Gly in the various yeast extracts was several ppm at most.
  • the amount of each of ⁇ -Glu-Val and Val-Gly was on the order of several tens of ppm at most.
  • the Saccharomyces cerevisiae S288C strain was used as a standard, and the Saccharomyces cerevisiae AJ14819 strain (deposited as an international deposit as FERM BP-08502 strain) was used for it's high GSH content.
  • the S288C strain is stored at the independent administrative agency, National Institute of Technology and Evaluation, Biological Resource Center (NBRC, NITE Biological Resource Center, 2-5-8 Kazusakamatari, Kisarazu-shi, Chiba-ken, 292-0818, Japan) with the number of NBRC1136, and can be provided therefrom.
  • This strain is also stored at the American Type Culture Collection (12301 Parklawn Drive, Rockville, Md. 20852, United States of America) with the number of ATCC 26108, and can be provided therefrom.
  • the AJ14819 strain was obtained by mutagenizing a monoploid yeast strain obtained from a commercially available Saccharomyces cerevisiae strain with EMS, and then selecting a mutant strain in which expression of the MET25 gene is not suppressed by methionine.
  • the resulting strain was deposited at the independent administrative agency, Agency of Industrial Science and Technology, International Patent Organism Depository, Central 6, 1-1-1, Higashi, Tsukuba-shi, Ibaraki-ken, 305-8566, Japan) on Sep.
  • One loop of each of the aforementioned strains was inoculated into SD medium (50 ml in 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm.
  • Nitrogen Base of 10-fold concentration was obtained by dissolving a mixture of 1.7 g of Bacto Yeast Nitrogen Base w/o Amino Acids and Ammonium Sulfate (Difco) and 5 g of ammonium sulfate in 100 ml of sterilized water, adjusting the solution to about pH 5.2, and sterilizing the solution by filter filtration.
  • the supernatant was removed as much as possible, and the residual cells were suspended in 45 ml of Milli-Q water.
  • the cells were collected again by centrifugal separation, and resuspended in 45 ml of Milli-Q water. By repeating this operation 3 times in total, the medium was completely removed from the cells.
  • the washed cells were suspended in about 1.5 ml of Milli-Q water, and the suspension was heated at 70° C. for 10 minutes. By this step, the extractable components contained in the cells were extracted. Then, the extract and the cell residue were separated by centrifugation.
  • One loop of the S288C strain was inoculated into the SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the obtained culture broth was measured, the culture broth was inoculated into SD medium (400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. for 16 hours with shaking by rotation at a velocity of 120 rpm. To the SD medium, ⁇ -Glu-Val-Gly (purchased from Kokusan Chemistry) was added in advance at a final concentration of 100 ppm.
  • One loop of the S288C strain was inoculated into SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the obtained culture broth was measured, the culture broth was inoculated into SD medium (400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. for 19 hours with shaking by rotation at a velocity of 120 rpm.
  • a yeast extract was produced from yeast cells cultured with the addition of ⁇ -Glu-Val-Gly.
  • One loop of the S288C strain was inoculated into SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the obtained culture broth was measured, the culture broth was inoculated into SD medium (400 ml in a 2 L-volume conical flask with baffle fins, 12 flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. for 19 hours with shaking by rotation at a velocity of 120 rpm. After 19 hours, a ⁇ -Glu-Val-Gly aqueous solution was added at a final concentration of 50 ppm, and the culture was continued for 1 hour.
  • the cells were collected from the total culture broth, and washed in the same manner as that of Example 2.
  • the washed cells in an amount of 400 OD units were suspended in 1.5 ml of Milli-Q water. This suspension was maintained at 70° C. for 10 minutes to produce an extract from the yeast cells. Furthermore, the suspension was centrifuged to remove the cell residues and thereby collect only the extract.
  • the ⁇ -Glu-Val-Gly concentration of this extract was measured to be about 300 ppm, and solid content was about 1%.
  • the ⁇ -Glu-Val-Gly concentration in an extract prepared in the same way but without adding ⁇ -Glu-Val-Gly to the culture broth (extract of no addition experiment) was below the quantitation limit, and solid content was about 1%.
  • the extracts prepared as described above were evaluated for kokumi in the presence of MSG (sodium glutamate) as follows.
  • MSG sodium glutamate
  • an aqueous solution containing 0.2% MSG and 0.5% NaCl was used, and the organoleptic score thereof was defined to be 0.0.
  • an aqueous solution containing 0.2% MSG, 0.5% NaCl and 10 ppm of ⁇ -Glu-Val-Gly was used as a standard solution for kokumi, and the organoleptic score thereof was defined to be 3.0.
  • the kokumi intensity of the extract was evaluated using an aqueous solution containing the extract, 0.2% MSG, and 0.5% NaCl as a test sample.
  • the amount of the extract of the addition experiment in the test sample was adjusted so that the ⁇ -Glu-Val-Gly concentration became 10 ppm.
  • the amount of the extract of the no addition experiment was adjusted so that the solid content in the test sample was the same as that in the test sample of the extract of the addition experiment.
  • the test samples prepared as described above were evaluated for kokumi by four special panelists. As a result, all four of the panelists evaluated that kokumi obtained with the extract of the addition experiment was stronger than that obtained with the same concentration of ⁇ -Glu-Val-Gly. Furthermore, kokumi was evaluated at different stages of tasting, that is, it was evaluated for initial and middle tastes and also for aftertaste. The averages of the scores of the four panelists for each type of kokumi were used as the evaluation scores. The results are shown in Table 5. The initial and middle tastes means the taste sensed at 0 to 4 seconds after eating, and the aftertaste means the taste sensed 5 seconds after eating and thereafter.
  • One loop of the S288C strain was inoculated into SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the resulting culture broth was measured, the culture broth was inoculated into SD medium (400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. for 24 hours with shaking by rotation at a velocity of 120 rpm. To the SD medium, ⁇ -Glu-Val (purchased from Bachem) was added in advance to a final concentration of 100 ppm. Using the culture broth, the amounts of ⁇ -Glu-Val and ⁇ -Glu-Val-Gly present in dry cells were calculated in the same manner as that of Example 2. The results are shown in Table 6.
  • One loop of the S288C strain was inoculated into SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the resulting culture broth was measured, the culture broth was inoculated into SD medium (400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. for 19 hours with shaking by rotation at a velocity of 120 rpm.
  • One loop of the S288C strain was inoculated into SDP medium (ammonium sulfate used for the preparation of the SD medium was replaced with proline, final concentration of proline was 0.1 g/L, 50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the resulting culture broth was measured, the culture broth was inoculated into SDP medium (400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C.
  • SDP medium 400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks
  • a 1% aqueous solution of the yeast extract containing about 8% of GSH based on the solid content was prepared, and adjusted to pH 7.0 with NaOH. To this solution, powdered Val-Gly was added to final concentrations in the aqueous solutions of 400 ppm, 800 ppm and 4000 ppm to prepare test samples. An aqueous solution of the yeast extract without addition of Val-Gly was also used as a control.
  • a glutaminase (Glutaminase Daiwa SD-C100S, Daiwa kasei) was added at 1 mg/ml, and the enzymatic reaction was allowed at 37° C. for 120 minutes.
  • ⁇ -GTP ⁇ -Glutamyltranspeptidase from equine kidney, Sigma, Code G9270-100UN was added at 0.05 mg/ml instead of the glutaminase, and the enzymatic reaction was similarly allowed at 37° C. for 120 minutes.
  • the reaction mixtures were immediately cooled on ice, and the amounts of ⁇ -Glu-Val-Gly, GSH and Cys-Gly were measured.
  • Val or nVal is added instead of Val-Gly, and the enzyme reaction is allowed to proceed in a similar manner, ⁇ -Glu-Val or ⁇ -Glu-nVal is also produced.
  • a GSH2 expression-enhanced strain can be bred by the following procedure.
  • a uracil auxotrophic strain can be obtained by spreading a Saccharomyces cerevisiae strain treated with a mutagen in a conventional manner on an agar medium containing 5-FOA, and selecting an ura3 mutant strain from the strains that grow (see, for example, METHODS IN YEAST GENETICS, 2000 EDITION, p. 179).
  • a uracil auxotrophic strain can also be obtained by introducing an URA3-neighboring DNA except for the URA3 gene into the S288C strain, and disrupting the URA3 gene, as shown below.
  • a 500-bp upstream region of URA3 was amplified by PCR using the primers shown in SEQ ID NOS: 1 and 2, and the chromosomal DNA of the S288C strain as the template. Furthermore, a 500-bp downstream region of URA3 was also amplified using the primers shown in SEQ ID NOS: 3 and 4.
  • PCR conditions a cycle consisting of thermal denaturation at 94° C. for 10 seconds, annealing at 55° C. for 10 seconds, and extension at 72° C. for 1 minute was repeated 25 times.
  • the URA3 locus was amplified by PCR using the primers of SEQ ID NOS: 7 and 8 and the chromosomal DNA of a Saccharomyces cerevisiae wild-type strain as the template (thermal denaturation: 94° C. for 10 seconds, annealing: 50° C. for 10 seconds, extension: 72° C. for 1 minute, 25 cycles).
  • the resulting DNA fragment was purified by ethanol precipitation, and then digested with SphI and EcoRI, and the product was inserted into the plasmid pUC19 at the SphI-EcoRI sites to obtain pUC19-URA3.
  • the PGK1 promoter region was amplified from the chromosomal DNA of the Saccharomyces cerevisiae wild-type strain using the primers shown in SEQ ID NOS: 9 and 10. This DNA fragment was digested with PstI, and inserted into pUC19-URA3 digested with PstI and treated with CIAP at the PstI site to obtain pUC19-PGK1p-URA3.
  • the PGK1 promoter amplified using the primers shown in SEQ ID NOS: 11 and 12 was digested with AatII, and inserted into pUC19-PGK1p-URA digested with AatII and treated with CIAP at the AatII site to obtain pUC19-PGK1p-URA3-PGK1p.
  • the nucleotide sequence of the prepared template plasmid was confirmed by sequencing, it was equivalent to the nucleotide sequence expected when using the chromosomal DNA of the S288C strain as the template. Therefore, even if the chromosomal DNA of the S288C strain is used as the template instead of chromosomal DNA of a wild-type strain, a similar plasmid can be prepared.
  • PCR is performed using the primer of SEQ ID NO: 13, which has a GSH2 upstream sequence at the 5′ end, the primer of SEQ ID NO: 14, which has a part of a sequence in ORF starting from the start codon of the GSH2 gene, and pUC19-PGK1p-URA3-PGK1p as the template (thermal denaturation: 94° C. for 10 seconds, annealing: 60° C. for 10 seconds, extension: 72° C. for 4 minutes, 25 cycles) to prepare a DNA fragment having URA3 between PGK1 promoters.
  • the ura3 ⁇ 0 strain can be transformed with this DNA fragment, and plated on an SD plate medium to obtain transformants, and a strain in which the GSH2 promoter is replaced with the PGK1 promoter-URA3-PGK1 promoter can be obtained from the transformants.
  • the strain in which the PGK1 promoter-URA3-PGK1 promoter substitutes for the GSH2 promoter is cultured overnight in a uracil-supplemented SD medium, and an appropriate volume of the culture is applied to 5-FOA plate medium. From colonies that appeared, a strain in which URA3 is removed by homologous recombination between the introduced PGK1 promoters, and the GSH2 promoter is replaced with the PGK1 promoter, can be obtained.
  • a strain with a genotype that is the same as that of the ura3 ⁇ 0 strain except that URA3 is returned to wild-type, and the GSH2 promoter is replaced with the PGK1 promoter can be obtained.
  • a yeast extract is produced from the strain obtained as described above, and evaluated in the same manner as described in Examples 3, 4, and 6 to 8.
  • An HGT1 expression-enhanced strain can be obtained in the same manner as described in Example 10. Specifically, by performing PCR using pUC19-PGK1p-URA3-PGK1p as a template, the primer of SEQ ID NO: 17, which has a GSH1 upstream sequence at the 5′ end, and the primer of SEQ ID NO: 18, which has a part of a sequence in ORF starting from the start codon of the GSH11 gene, and introducing the obtained DNA fragment into sporulating yeast, cells in which the promoter of GSH11 is replaced with the PGK1 promoter are obtained.
  • a yeast extract is produced from the strain obtained as described above, and evaluated in the same manner as described in Examples 3, 4, and 6 to 8.
  • Hgt1p which has been considered to be a GSH specific transporter
  • Ptr2p which is a peptide transporter
  • the geneticin (G418)-resistance cassette (P ADH1 -kanR) was amplified by PCR using pUC19AOX-G418-BRI ( FIG. 3 , SEQ ID NO: 23, Olga A. et al., Mol. Biotechnol., Pubslished online Dec. 19, 2010)) as the template and primers URA3 Km-L1 (SEQ ID NO: 24) and URA3 Km-R2 (SEQ ID NO: 25).
  • the plasmid pUC19AOX-G418-BRI consists of the kanamycin resistant gene (neo) from E. coli transposon Tn5 under control of S.
  • ADC1 cerevisiae ADH1 (ADC1) promoter cloned in pUC19 vector.
  • BR1 means that in this plasmid the BamHI and EcoRI sites, which are present in parental pUC19AOX-G418 between P ADH1 and kaznR, were deleted.
  • the P ADH1 -kanR cassette or its equivalent can also be obtained by PCR using the plasmid pKat7 (Lang-Hinrichs, C. et al., 1989. Applied Microbiology and Biotechnology. 30:388-394) or pUM2 (Merckelbach A, et al., 1993, Appl Microbiol Biotechnol. November; 40:361-364) instead of pUC19AOX-G418-BRI as a template and the above described primers URA3Km-L1 and URA3Km-R2.
  • 40 nucleotides at 5′-end of primer URA3 Km-L1 are homologous to the URA3 upstream region, and 40 nucleotides at 5′-end of primer URA3 Km-R2 are complementary to the URA3 downstream region.
  • the resulting DNA fragment was used for transformation of S. cerevisiae S288C. Transformants were selected on YPD plates containing 200 ⁇ g/ml of G418. Deletion of the URA3 gene was verified by PCR with primers ura3up2 (SEQ ID NO: 26) and ura3dn2 (SEQ ID NO: 27).
  • the resulting strain was S288C ura3 ⁇ 0::P ADH1 -kanR. It may also be referred to as S288C ura3 ⁇ 0. This strain was used to construct a HGT1 or PTR2 overxpressing strain.
  • uracil auxotrophic mutant was acquired as follows in order to use it to construct a strain in which HGT1 or PTR2 is deleted.
  • a fragment which contains URA3 with promoter and terminator regions was amplified by PCR using chrojmosomal DNA of S288C as the template and the aforementioned primers ura3up2 and ura3dn2.
  • This fragment was cloned into the SmaI site of pBluescript II KS (+), and its structure was confirmed by sequencing analysis.
  • the resulting plasmid was referred to as pKS-URA3-13 ( FIG. 4 , SEQ ID NO: 28).
  • Plasmid pKS-URA3-13 was digested with StuI and NcoI, and then treated with Klenow fragment to blunt-end the NcoI site. The resulting 4.38-kb fragment was ligated with the 1.64-kb HincII-HincII fragment from pUG6 [Güldener, U., Heck, S., Fiedler, T., Beinhauer, J., and Hegemann, J.H.1996. A new efficient gene disruption cassette for repeated use in budding yeast. Nucleic Acids Research 24, 2519-2524], containing a loxP-kanMX-loxP module. The resulting plasmid was referred to as pKS-URA3-13-kanMX. Its map and scheme of construction is shown in FIG. 5 , SEQ ID NO: 29.
  • the kanMX gene flanked by URA3 fragments was amplified by PCR using the aforementioned primers ura3up2 and ura3dn2, and pKS-URA3-13-kanMX as the template.
  • the resulting fragment was used for transformation of S. cerevisiae S288C strain, and then transformants were selected on YPD medium containing 200 ⁇ g/ml of G418.
  • a S288C derivative strain with deletion of 227 nucleotides of coding region of URA3 was obtained. This deletion was referred to as ura3 ⁇ 227::loxP-kanMX-loxP.
  • the resulting strain was transformed with plasmid pSH47 [Güldener, U., Heck, S., Fiedler, T., Beinhauer, J., and Hegemann, J.H.1996.
  • plasmid pSH47 [Güldener, U., Heck, S., Fiedler, T., Beinhauer, J., and Hegemann, J.H.1996.
  • Nucleic Acids Research 24, 2519-2524 containing a gene encoding Cre-recombinase under the control of the GAL1 promoter and URA3 as a selective marker.
  • Marker excision occurred after induction of Cre-recombinase synthesis by shifting cells from the YPD medium to YPG (containing galactose).
  • the resulting strain from which the plasmid pSH47 had been deleted was designated S288C ura3 ⁇ 227::loxP.
  • DNA fragment containing an Agleu2-CaURA3-Agleu2 cassette was amplified by PCR using plasmid pAG61 [Goldstein, A. L., Pan, X., and McCusker, J.H.1999. Heterologous URA3MX cassettes for gene replacement in Saccharomyces cerevisiae . Yeast 15, 507-511] as the template and primers hgt1-pUG6u (SEQ ID NO: 30) and hgt1-pUG6d (SEQ ID NO: 31).
  • the Agleu2-CaURA3-Agleu2 cassette contains Candida albicans URA3 gene under control of Ashbya gossypii TEF promoter and terminator, surrounded with two identical fragments of Ashbya gossypii LEU2 gene.
  • Each of the LEU2 gene fragments is a 470 bp sequence spanning from C-terminal region to 3′ UTR of the gene.
  • the Agleu2-CaURA3-Agleu2 cassette is excisable from the plasmid pAG61.
  • nucleotides at the 5′-end of primer hgt1-pUG6u are homologous to the HGT1 5′-region, and 44 nucleotides at the 5′-end of the primer hgt1-pUG6d are complementary to the HGT1 3′-region.
  • the resulting fragment was used for transformation of the S288C ura3 ⁇ 227::loxP strain. Transformants were selected on plates containing SD medium.
  • HGT1 gene was verified by PCR using the primers hgt1-51 (SEQ ID NO: 32) and hgt1-32 (SEQ ID NO: 33).
  • the P ADH1 -kanR module from plasmid pUC19AOX-G418-BRI was excised with XbaI and SacI and subcloned into the same sites of plasmid pUG6.
  • the resulting plasmid was referred to as pLoxP-PADH1-kanR5 ( FIG. 6 ).
  • a DNA fragment containing the loxP-P ADH1 -kanR-loxP module was amplified by PCR using the pLoxP-PADH1-kanR5 plasmid as the template and primers ptr2-pUG6u (SEQ ID NO: 34) and ptr2-pUG6d (SEQ ID NO: 35).
  • nucleotides at the 5′-end of primer hgt1-pUG6u are homologous to the PTR2 5′-region, and 44 nucleotides at the 5′-end of primer hgt1-pUG6d are complementary to the PTR23′-region.
  • the resulting fragment was used for transformation of S288C ura3 ⁇ 227::loxP strain. Transformants were selected on plates containing YPD medium with 200 ⁇ g/ml of G418.
  • the deletion of the PTR2 gene was verified by PCR using primers ptr2-51 (SEQ ID NO: 36) and ptr2-31 (SEQ ID NO: 37).
  • strain S288C hgt1 ⁇ ptr2 ⁇ was constructed in a manner similar to the S288C ptr2 ⁇ strain, but the strain S288C hgt1 ⁇ was used for transformation.
  • a DNA fragment containing the promoter of ADH1 was amplified by PCR using chromosomal DNA of S. cerevisiae strain S288C as the template and primers adh1L1 (SEQ ID NO: 38) and adh1R1 (SEQ ID NO: 39).
  • the resulting fragment was cloned into the SmaI site of plasmid pUC19 and its structure was confirmed by sequence analysis.
  • the resulting plasmid was referred to as pUC19-PADH1-r ( FIG. 7 ).
  • the HindIII-HindIII fragment (1.16 kb) from the plasmid pKS-URA3-13 was subcloned into the HindIII site of the plasmid pBluescript II KS(+) yielding pKS-URA3H-d.
  • the KpnI-SalI fragment from the plasmid pUC19-PADH1-r was cloned into the SalI-KpnI sites of pKS-URA3H-d.
  • the resulting plasmid was referred to as pKS-URA3-P-ADH1 ( FIG. 8 ).
  • plasmid pKS-URA3-PADH1 was digested with ClaI and BsrGI.
  • the digested plasmid was blunt-ended with Klenow fragment and self-ligated.
  • the resulting plasmid referred to as pKS-URA3-PADH1-5′ d, was digested with EcoPJ, treated with Klenow fragment, and then digested with)(bal.
  • the resulting fragment was ligated with a fragment of P ADH1 , and excised from plasmid pUC19-PADH1-r with XbaI and BstZ17I.
  • the resulting plasmid was referred to as pKS-URA3-PADH1-LR ( FIG. 7 ).
  • a DNA fragment containing a P ADH1 -URA3-P ADH1 cassette was amplified by PCR using the plasmid pKS-URA3-PADH1-LR as the template and primers PADH1-HGT1 (SEQ ID NO: 40) and HGT1-PADH1 (SEQ ID NO: 41).
  • 40 nucleotides at the 5′-end of primer PADH1-HGT1 are complementary to the first 40 nucleotides of the HGT1 coding region, and 40 nucleotides at the 5′-end of primer HGT1-PADH1 are homologous to the HGT1 upstream region.
  • a DNA fragment containing the HGT1 upstream region was amplified by PCR using chromosomal DNA of S. cerevisiae strain S288C as the template and primers hgt53 (SEQ ID NO: 42) and hgt33 (SEQ ID NO: 43).
  • fragments obtained as described above were fused by PCR using primers hgt53 and PADH1-HGT1 as it was described in Shevchuk, N. A., Bryksin, A. V., Nusinovich, Y. A., Cabello, F. C., Sutherland M., Ladisch S. 2004. Construction of long DNA molecules using long PCR-based fusion of several fragments simultaneously. Nucleic Acids Res. 32(2):e19. The resulting fragment was used for transformation of strain S288C ura3 ⁇ 0::P ADH1 -kanR. Transformants were selected on plates containing SD medium.
  • strain S288C ura3 ⁇ 0::P ADH1 -kanR P ADH1 -URA3-P ADH1 -HGT1 was obtained. It was referred to as S288C P ADH1 -HGT1.
  • Primer hgt53 corresponds to Primer1
  • primer hgt33 corresponds to Primer2
  • primer HGT1-PADH1 corresponds to Primer3
  • primer PADH1-HGT1 corresponds to Primer4.
  • ptr52 (SEQ ID NO: 44), correspond to Primer1;
  • ptr32 (SEQ ID NO: 45), correspond to Primer2;
  • PTR2-PADH1 (SEQ ID NO: 46), correspond to Primer4;
  • PADH1-PTR2 (SEQ ID NO: 47), correspond to Primer3;
  • primer PADH1-PTR2 are complementary to the first 40 nucleotides of the PTR2 coding region, and 30 nucleotides at the 5′-end of the primer PTR2-PADH1 are homologous to the PTR2 upstream region.
  • the aqueous phase was transferred to a clean vial and the vial was then vacuum-dried. Thus, a dried extract was prepared. Then, the amount of ⁇ -Glu-Val-Gly in the dried extract was measured with LC-MS/MS analysis. The detailed procedures are described below.
  • intracellular content of ⁇ -Glu-Val-Gly in S288C on the dry weight cell was about 0.9%, but intracellular content of ⁇ -Glu-Val-Gly in S288C P ADH1 -HGT1 on the dry weight cell was about 4.9%. This result confirms the effect of Hgt1p overproduction.
  • ⁇ -Glu-nVal-Gly uptake ability of S288C was evaluated in the same manner as described in example 4.
  • ⁇ -Glu-nVal-Gly was added into the medium in advance at a final concentration of 10 ppm or 100 ppm.
  • the ⁇ -Glu-nVal-Gly content was measured in the same manner described in experimental example 1 by using 1 ⁇ M ⁇ -Glu-nVal-Gly as a standard solution instead of ⁇ -Glu-Val-Gly.
  • the ⁇ -Glu-nVal-Gly content in the dry cell was under the quantitative limit when ⁇ -Glu-nVal-Gly was not added into the medium, but ⁇ -Glu-nVal-Gly content in the dry cell was about 0.07% when ⁇ -Glu-nVal-Gly was added into the medium at a final concentration of 10 ppm, and ⁇ -Glu-nVal-Gly content in the dry cell was about 0.09% when ⁇ -Glu-nVal-Gly was added into the medium at a final concentration of 100 ppm.
  • the analysis result (HPLC-MS chromatogram) of derivatized ⁇ -Glu-nVal-Gly standard sample is shown in FIG. 2 .
  • ⁇ -Glu-nVal uptake ability of S288C was evaluated in the same manner as described in example 7.
  • ⁇ -Glu-nVal was added in advance at a final concentration of 10 ppm or 100 ppm.
  • the ⁇ -Glu-nVal content was measured in the same manner described in the experimental example 1 by using 1 ⁇ M ⁇ -Glu-nVal as a standard solution instead of ⁇ -Glu-Val.
  • the ⁇ -Glu-nVal content in the dry cell was under the quantitative limit when ⁇ -Glu-nVal was not added into the medium, but ⁇ -Glu-nVal content in the dry cell was about 0.03% when ⁇ -Glu-nVal was added into the medium at a final concentration of 10 ppm, and ⁇ -Glu-nVal content in the dry cell was about 0.13% when ⁇ -Glu-nVal was added into the medium at a final concentration of 100 ppm.
  • a yeast extract was produced from yeast cells cultured with addition of ⁇ -Glu-nVal-Gly in the same manner as described in example 5.
  • One loop of the S288C strain was inoculated into SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the resulting culture broth was measured, the culture broth was inoculated into SD medium (400 ml in a 2 L-volume conical flask with baffle fins, 12 flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. for 19 hours with shaking by rotation at a velocity of 120 rpm. After 19 hours, a ⁇ -Glu-nVal-Gly solution was added to a final concentration of 50 ppm, and the culture was continued for 1 hour.
  • the cells were collected from the obtained total culture broth, and washed in the same manner as described in Example 2.
  • the washed cells in an amount of 400 OD units were suspended in 1.5 ml of Milli-Q water. This suspension was maintained at 70° C. for 10 minutes to produce an extract from the yeast cells. Furthermore, the suspension was centrifuged to remove the cell residues and thereby collect only the extract.
  • the ⁇ -Glu-nVal-Gly concentration of this extract was measured to be about 100 ppm, and the solid content was about 1%.
  • the ⁇ -Glu-nVal-Gly concentration of an extract prepared by the same operation without adding ⁇ -Glu-nVal-Gly to the culture broth (extract of no addition experiment) was below the detection limit, and the solid content was about 1%.
  • the extracts prepared as described above were evaluated for kokumi in the presence of MSG (sodium glutamate) as follows.
  • MSG sodium glutamate
  • an aqueous solution containing 0.2% MSG and 0.5% NaCl was used, and the organoleptic score thereof was defined to be 0.0.
  • an aqueous solution containing 0.2% MSG, 0.5% NaCl and 1 ppm of ⁇ -Glu-nVal-Gly was used as a standard solution for kokumi, and the organoleptic score thereof was defined to be 3.0.
  • the kokumi intensity of the extracts was evaluated using an aqueous solution containing the extract, 0.2% MSG and 0.5% NaCl as a test sample.
  • the amount of the extract of the addition experiment in the test sample was adjusted so that the ⁇ -Glu-nVal-Gly concentration became 1 ppm.
  • the amount of the extract of the no addition experiment was adjusted so that the solid content in the test sample was the same as that in the test sample of the extract of the addition experiment. That is, the ⁇ -Glu-nVal-Gly concentrations in the standard solution of kokumi and the test sample containing the extract of the addition experiment were equivalent, and the solid contents in the test sample containing the extract of the addition experiment and the test sample containing the extract of the no addition experiment, were equivalent.
  • a model sample was prepared by adding a ⁇ -Glu-nVal-Gly solution into the extract of no addition experiment so as to be at an equivalent concentration of ⁇ -Glu-nVal-Gly as compared to the extract of addition experiment. Therefore the ⁇ -Glu-nVal-Gly concentration contained in the model sample was about 100 ppm, and the solid content was about 1%.
  • the test samples prepared as described above were evaluated for kokumi by four special panelists. As a result, all four of the panelists evaluated that kokumi obtained with the extract of the addition experiment was stronger than that obtained with the same concentration of ⁇ -Glu-nVal-Gly. Furthermore, kokumi was evaluated for initial and middle tastes, and for aftertaste. Averages of the scores of the four panelists for each taste point of kokumi were used as the evaluation scores. The results are shown in Table 15. The initial and middle tastes means the taste at 0 to 4 seconds after eating, and the aftertaste means the taste 5 seconds after eating and thereafter.
  • S288C P ADH1 -HGT1, Hgt1p overproducing strain obtained in Example 12, and its parental strain S288C were evaluated for their ⁇ -Glu-nVal-Gly uptake abilities in the same manners as described in Example 4 and Example 13.
  • the amount of ⁇ -Glu-nVal-Gly added to the medium was 100 ppm as a final concentration.
  • intracellular content of ⁇ -Glu-Val-Gly in S288C on the dry weight cell was about 0.09%, but intracellular content of ⁇ -Glu-nVal-Gly in S288C P ADH1 -HGT1 on the dry weight cell was about 2.84%.
  • S288C P ADH1 -HGT1, Hgt1p overproducing strain obtained in Example 12, S288C P ADH1 -PTR2, Ptr2p overproducing strain obtained in Example 12, and their parental strain S288C were evaluated for their ⁇ -Glu-Val-Gly producing abilities from Val-Gly.
  • S288C strain was cultivated in SDP medium in the same manner as the Val-Gly no addition experiment described in Example 8. Then, cellular ⁇ -Glu-nVal-Gly and ⁇ -Glu-nVal were measured but were below the detection limit Therefore, the effect of addition of nVal to the GSH1 overexpressing strain was evaluated.
  • GSH1 overexpressing strain was constructed as described below.
  • Uracil auxotrophic strain (ura3 mutant) was obtained in the same manner described in Example 10, but a Saccharomyces cerevisiae wild type strain (MAT a type haploid strain) was used instead of S288C strain.
  • the resulting strain was given a private number AJ14956, and was deposited at the independent administrative agency, Agency of Industrial Science and Technology, International Patent Organism Depository (Tukuba Central 6, 1-1, Higashi 1-chome, Tsukuba-shi, Ibaraki-ken, 305-8566, Japan) on Aug. 18, 2010, and assigned an accession number of FERM P-22000. Then, the deposit was converted to an international deposit under the provisions of the Budapest Treaty on Nov. 17, 2010, and assigned an accession number of FERM BP-11299.
  • this AG1 strain was cultivated in SD medium supplemented with nVal. More specifically, one loop of the AG1 strain was inoculated into SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the obtained culture broth was measured, and the culture broth was inoculated into SDP medium (400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. for 23 hours with shaking by rotation at a velocity of 120 rpm.
  • SDP medium 400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks
  • nVal solution was added to a final concentration of 10 ppm or 100 ppm, and the cultures were continued for 1 hour. Then, the amount of ⁇ -Glu-nVal was measured in the same manner described in the experimental example 15. The ⁇ -Glu-nVal content was 0.07% when 10 ppm of nVal was added to the medium and the ⁇ -Glu-nVal content was 0.37% when 100 ppm of nVal was added to the medium. Then, yeast extract containing ⁇ -Glu-nVal was prepared from the broth culture cultivated with 100 ppm nVal basically in the same manner as described in Example 16. This yeast extract contained 1.44% ⁇ -Glu-nVal at the dry matter base. This yeast extract would give strong kokumi for initial and middle taste from its character.
  • GSH2 overexpressing strain PG2 was constructed basically in the same manner as described in Example 10 except that AJ14956 described in Example 19 was used instead of ura3 ⁇ 0 from S288C. As a control, WT strain was obtained by returning the deleted URA3 gene into wild type gene from AJ14956 in the same manner described in Example 10 and Example 19.
  • One loop of the WT strain or PG2 strain was inoculated into SD medium (50 ml in a 500 ml-volume Sakaguchi flask), and cultured at 30° C. for 24 hours with shaking at a velocity of 120 rpm. Absorbance of the obtained culture broth was measured, and the culture broth was inoculated into the SD medium supplemented with various concentrations of ⁇ -Glu-Val (400 ml in a 2 L-volume conical flask with baffle fins, two or more flasks) so that OD660 was 0.01 at the start of the culture, and culture was performed at 30° C. with shaking by rotation at a velocity of 120 rpm until OD660 reached to the predetermined value.
  • the DNA fragment containing promoter of the TDH3 gene, encoding the glyceraldehyde 3-phosphate dehydrogenase was amplified by PCR, using the chromosomal DNA of S288C strain as a template, and tdh3-EcoR1 (SEQ ID NO: 48) and tdh3-Pci1 (SEQ ID NO: 49) primers (thermal denaturation: 94° C. for 20 seconds, annealing: 50° C. for 20 seconds, extension: 72° C. for 30 seconds, 30 cycles). Resulting fragment was cloned into SmaI site of pUC57 vector.
  • the plasmid where promoter of TDH3 gene was orientated in direction from HindIII site to EcoRI site was selected and referred to as pUC57-PTDH3.
  • the structure of cloned DNA fragment was confirmed by sequence analysis.
  • the NdeI-SalI DNA fragment of pUC57-PTDH3 was cloned into NdeI-SalI sites of pUG6 (Güldener, U., Heck, S., Fiedler, T., Beinhauer, J., and Hegemann, J. H. 1996. A new efficient gene disruption cassette for repeated use in budding yeast. Nucleic Acids Research 24, 2519-2524). Resulting plasmid was referred to as pUG6-PTDH3 ( FIG. 10 ).
  • the loxP-kanMX-loxP-P TDH3 cassette was amplified by PCR using the pUG6-PTDH3 as a template and GSH1-pUG (SEQ ID NO: 50) and PTDH3-GSH1 (SEQ ID NO: 51) primers (thermal denaturation: 94° C. for 20 seconds, annealing: 48° C. for 60 seconds, extension: 72° C. for 120 seconds, 2 cycles; 94° C. for 20 seconds, annealing: 65° C. for 20 seconds, extension: 72° C. for 120 seconds, 20 cycles). Resulting DNA fragment was used for transformation of S288C strain. Transformants were selected on YPD medium containing 200 ⁇ g/ml of G418.
  • the S288C derivative strain with promoter of GSH1 gene replaced with promoter of TDH3 was obtained (S288C loxP-kanMX-loxP-P TDH3 -GSH1 strain).
  • the ura3 derivative of this strain (S288C ura3 loxP-kanMX-loxP-P TDH3 -GSH1 strain) was obtained then, by selection on 5-FOA containing medium according conventional method (see, for example, METHODS IN YEAST GENETICS, 2000 EDITION, p. 179).
  • the kanMX marker was deleted from resulting strain by means of transformation by pSH47 plasmid, as it is described in Example 12.
  • the S288C ura3 loxP-P TDH3 -GSH1 strain was obtained.
  • the native promoter of GSH2 gene was then replaced with promoter of TDH3.
  • the loxP-kanMX-loxP-P TDR3 cassette was amplified by PCR using the pUG6-PTDH3 as a template and PTDH3-GSH2 (SEQ ID NO: 52) and GSH2-pUG (SEQ ID NO: 53) primers (thermal denaturation: 94° C. for 20 seconds, annealing: 48° C. for 60 seconds, extension: 72° C. for 120 seconds, 2 cycles; 94° C. for 20 seconds, annealing: 65° C. for 20 seconds, extension: 72° C. for 120 seconds, 20 cycles).
  • the GSH2 upstream region was amplified by PCR using chromosomal DNA of S288C strain as a template and GSH2up2 (SEQ ID NO: 54) and GSH2d_tail (SEQ ID NO: 55) primers (thermal denaturation: 94° C. for 20 seconds, annealing: 48° C. for 20 seconds, 72° C. for 30 seconds, 30 cycles).
  • the resulting fragments were fused by means of overlap extension PCR (Shevchuk, N. A. at al. 2004. Construction of long DNA molecules using long PCR-based fusion of several fragments simultaneously. Nucleic Acids Res.
  • the kanMX marker was deleted from this strain as was described above, and the S288C ura3 loxP-P TDH3 -GSH1 loxP-P TDH3 -GSH2 strain was obtained. It was referred to as Y3560.
  • the P TDH3 -GSH2 construction was amplified using Y3560 chromosomal DNA as a template and yepgsh2-F (SEQ ID NO: 56) and yepgsh2-R (SEQ ID NO: 57) primers.
  • the 45 nucleotides of 5′ sequences of these primers were complementary to regions flanking the SmaI-BamHI fragment in YEp24 plasmid ( FIG. 11 ).
  • the YEp24 plasmid was digested with SmaI and BamHI and the larger of the resulting fragments were isolated by means of agarose gel electrophoresis.
  • the resulting P TDH3 -GSH2 and YEp24 fragments were mixed and used for transformation of S288C ura3 ⁇ 227::loxP and Y3560 strains. Transformants were selected on SD medium. Resulting plasmid was referred to as YEp24-PTDH3-GSH2, and resulting strains were referred to as S288C ura3 ⁇ 227/YEp24-PTDH3-GSH2 and Y3560/YEp24-PTDH3-GSH2, respectively.
  • Each of the S288C ura3 ⁇ 227/YEp24-PTDH3-GSH2, Y3560/YEp24-PTDH3-GSH2, S288C and Y3560 strains was cultivated in 50-ml tubes containing 10 ml of SD medium with 100 ppm ⁇ -Glu-Val as a final concentration.
  • GSH2 overexpressing strains converted ⁇ -Glu-Val into ⁇ -Glu-Val-Gly in the cell.

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2783413C (fr) * 2009-12-28 2014-02-18 Ajinomoto Co., Inc. Agent conferant du kokumi
CN103348014B (zh) 2010-10-05 2020-11-03 味之素株式会社 含有γ-Glu-Abu的酵母和酵母提取物以及它们的制备方法
JP6324070B2 (ja) * 2011-08-30 2018-05-16 三菱商事フードテック株式会社 砂糖様甘味質を有する甘味料及びそれを用いた飲食物
FR2980483B1 (fr) * 2011-09-23 2015-07-17 Lesaffre & Cie Souches de levure pour la production de glutathion
JP5998589B2 (ja) * 2012-04-02 2016-09-28 味の素株式会社 γ−Ｇｌｕ−Ｘを含有する酵母
WO2014017485A1 (fr) * 2012-07-25 2014-01-30 味の素株式会社 Aliment ou boisson contenant du jus de fruit
EP3020801A4 (fr) 2013-07-12 2017-01-18 Ajinomoto Co., Inc. LEVURE À FORTE TENEUR EN Abu, upsilon-Glu-Abu, ET/OU upsilon-Glu-Abu-Gly
CN106256266B (zh) * 2015-06-16 2020-02-07 安琪酵母股份有限公司 具有醇厚感口味的高蛋白酵母抽提物及其制法和应用
EP3797167B1 (fr) * 2018-05-23 2024-09-18 Ajinomoto Co., Inc. Méthode de production du tripeptide gamma-glu-val-gly à l'aide d'enterobacteriaceae
JP7197339B2 (ja) 2018-12-05 2022-12-27 アサヒグループ食品株式会社 コク味付与物質含有酵母の製造方法及びコク味付与物質含有酵母エキスの製造方法

Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54157890A (en) 1978-05-29 1979-12-13 Sapporo Breweries Production of microorganism cells
JPS6075279A (ja) 1983-10-03 1985-04-27 Ajinomoto Co Inc 微生物菌体の製造法
JPH02295480A (ja) 1989-05-09 1990-12-06 Ajinomoto Co Inc グルタチオン高含有酵母及びその製造方法
JPH0616702B2 (ja) 1990-06-07 1994-03-09 旭化成工業株式会社 高分子化セレン含有菌体の製造法
JPH08332081A (ja) 1995-06-08 1996-12-17 Oriental Yeast Co Ltd マグネシウム高含有酵母
RU2070875C1 (ru) 1992-01-22 1996-12-27 Сергей Федорович Соловьев Штамм дрожжей exophiala nigrum для производства стимулятора роста растений
US6013485A (en) 1996-05-07 2000-01-11 Thymopharma, Ag Low-molecular weight active ingredient extract from yeasts and method for producing it
US6143295A (en) 1995-05-10 2000-11-07 Thymopharma Ag Low- molecular active ingredient extract from yeasts and method for producing it
JP2004113155A (ja) 2002-09-27 2004-04-15 Ajinomoto Co Inc γ−グルタミルシステインの製造法
JP2004298014A (ja) 2003-03-28 2004-10-28 Japan Tobacco Inc ミネラル高含有パン酵母及びそれを用いたパン
US7118775B2 (en) * 1998-11-26 2006-10-10 Ajinomoto Co., Inc. Process for producing a flavor-enhancing material for foods
WO2007042288A2 (fr) 2005-10-14 2007-04-19 Thomas Frank Hofmann & Andreas Dunkel Composes saveur kokumi et utilisation de ceux-ci
WO2007055393A1 (fr) 2005-11-09 2007-05-18 Ajinomoto Co., Inc. Agent de distribution de kokumi
WO2007055388A2 (fr) 2005-11-09 2007-05-18 Ajinomoto Co., Inc. Activateur du recepteur du calcium
JP2008099578A (ja) 2006-10-18 2008-05-01 Medience Corp 亜鉛酵母およびその製造方法
WO2008139946A1 (fr) 2007-05-08 2008-11-20 Ajinomoto Co., Inc. Edulcorant
WO2009110624A1 (fr) 2008-03-04 2009-09-11 味の素株式会社 Levure produisant de la γ-glutamylcystéine, et procédé de fabrication de levure
US20090246835A1 (en) 2005-09-27 2009-10-01 Shintaro Iwatani l-amino acid-producing bacterium and a method for producing an l-amino acid
US20100136197A1 (en) 2005-11-09 2010-06-03 Yuzuru Eto Kokumi- imparting agent

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0675279A (ja) 1992-08-28 1994-03-18 Canon Inc カメラのフィルム給送装置
JP2002282743A (ja) 2001-03-28 2002-10-02 Satoerekkusu:Kk フィトンチッド抽出液の圧送噴霧装置
JP4273689B2 (ja) * 2001-11-26 2009-06-03 味の素株式会社 γ−グルタミルシステイン産生酵母
PE20031013A1 (es) 2002-03-26 2004-02-05 Ajinomoto Kk CANDIDA UTILIS QUE PRODUCE y-GLUTAMILCISTEINA
JP4352877B2 (ja) 2002-12-13 2009-10-28 味の素株式会社 γ−グルタミルシステインの製造法

Patent Citations (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54157890A (en) 1978-05-29 1979-12-13 Sapporo Breweries Production of microorganism cells
JPS6075279A (ja) 1983-10-03 1985-04-27 Ajinomoto Co Inc 微生物菌体の製造法
JPH02295480A (ja) 1989-05-09 1990-12-06 Ajinomoto Co Inc グルタチオン高含有酵母及びその製造方法
JPH0616702B2 (ja) 1990-06-07 1994-03-09 旭化成工業株式会社 高分子化セレン含有菌体の製造法
RU2070875C1 (ru) 1992-01-22 1996-12-27 Сергей Федорович Соловьев Штамм дрожжей exophiala nigrum для производства стимулятора роста растений
US6348335B1 (en) 1995-05-10 2002-02-19 Thymopharma, Ag Low-molecular active weight ingredient extract from yeasts and method for producing it
US6143295A (en) 1995-05-10 2000-11-07 Thymopharma Ag Low- molecular active ingredient extract from yeasts and method for producing it
JPH08332081A (ja) 1995-06-08 1996-12-17 Oriental Yeast Co Ltd マグネシウム高含有酵母
US6013485A (en) 1996-05-07 2000-01-11 Thymopharma, Ag Low-molecular weight active ingredient extract from yeasts and method for producing it
US7118775B2 (en) * 1998-11-26 2006-10-10 Ajinomoto Co., Inc. Process for producing a flavor-enhancing material for foods
JP2004113155A (ja) 2002-09-27 2004-04-15 Ajinomoto Co Inc γ−グルタミルシステインの製造法
JP2004298014A (ja) 2003-03-28 2004-10-28 Japan Tobacco Inc ミネラル高含有パン酵母及びそれを用いたパン
US20090246835A1 (en) 2005-09-27 2009-10-01 Shintaro Iwatani l-amino acid-producing bacterium and a method for producing an l-amino acid
WO2007042288A2 (fr) 2005-10-14 2007-04-19 Thomas Frank Hofmann & Andreas Dunkel Composes saveur kokumi et utilisation de ceux-ci
US20090130282A1 (en) 2005-10-14 2009-05-21 Givaudan Sa Kokumi Flavour Compounds and Use
WO2007055388A2 (fr) 2005-11-09 2007-05-18 Ajinomoto Co., Inc. Activateur du recepteur du calcium
US20090239310A1 (en) * 2005-11-09 2009-09-24 Takeaki Ohsu Kokumi-imparting agent
WO2007055393A1 (fr) 2005-11-09 2007-05-18 Ajinomoto Co., Inc. Agent de distribution de kokumi
US20100136197A1 (en) 2005-11-09 2010-06-03 Yuzuru Eto Kokumi- imparting agent
US20110097805A1 (en) 2005-11-09 2011-04-28 Takeaki Ohsu Kokumi-imparting agent
JP2008099578A (ja) 2006-10-18 2008-05-01 Medience Corp 亜鉛酵母およびその製造方法
WO2008139946A1 (fr) 2007-05-08 2008-11-20 Ajinomoto Co., Inc. Edulcorant
WO2009110624A1 (fr) 2008-03-04 2009-09-11 味の素株式会社 Levure produisant de la γ-glutamylcystéine, et procédé de fabrication de levure
EP2251413A1 (fr) 2008-03-04 2010-11-17 Ajinomoto Co., Inc. Levure produisant de la gamma-glutamylcystéine, et procédé de fabrication de levure

Non-Patent Citations (31)

* Cited by examiner, † Cited by third party
Title
A. Bourbouloux et al., "Hgt1p, a High Affinity Glutathione Transporter from the Yeast Saccharomyces cerevisiae*", The Journal of Biological Chemistry, vol. 275, No. 18, Apr. 28, 2000, pp. 13259-13265.
A. Dunkel, et al., "Molecular and sensory characterization of gamma-glutamyl peptides as key contributors to the kokumi taste of edible beans (Phaseolus vulgaris L.)", J. Argric. Food Chem., Aug. 8, 2007, vol. 55, pp. 6712-6719.
A. Dunkel, et al., "Molecular and sensory characterization of γ-glutamyl peptides as key contributors to the kokumi taste of edible beans (Phaseolus vulgaris L.)", J. Argric. Food Chem., Aug. 8, 2007, vol. 55, pp. 6712-6719.
Alton Meister et al., "Glutathione", Ann. Rev. Biochem., vol. 52, 1983, pp. 711-760.
Ana San Gabriel, et al., "The calcium-sensing receptor in taste tissue", Biochemical and Biophysical Research Communications, 378, 2009, pp. 414-418.
B. Volesky, et al., "Biosorption of heavy metals by Saccharomyces cerevisiae", Appl Microbiol Biotechnol, 42, 1995, pp. 797-806.
D. Ganguli et al., "The alternative pathway of glutathione degradation is mediated by a novel protein complex involving three new genes in Saccharomyces cerevisiae", Genetics, vol. 175, No. 3, Jan. 1, 2006, pp. 1137-1151.
G. Payne, et al., "gamma-Glutamyltransferase is not involved in the bulk uptake of amino acids, peptides or gamma-glutamyl-amino acids in yeast (Saccharomyces cerevisiae)", Biochem. J., Feb. 1, 1984, vol. 218, No. 1, pp. 147-155.
G. Payne, et al., "γ-Glutamyltransferase is not involved in the bulk uptake of amino acids, peptides or γ-glutamyl-amino acids in yeast (Saccharomyces cerevisiae)", Biochem. J., Feb. 1, 1984, vol. 218, No. 1, pp. 147-155.
Hideyuki Suzuki et al., "Use of Bacterial gamma-Glutamyltranspeptidase for Enzymatic Synthesis of gamma-d-Glutamyl Compounds", Applied and Environmental Microbiology, vol. 69, No. 11, 2003, pp. 6399-6404 and cover page.
Hideyuki Suzuki et al., "Use of Bacterial γ-Glutamyltranspeptidase for Enzymatic Synthesis of γ-d-Glutamyl Compounds", Applied and Environmental Microbiology, vol. 69, No. 11, 2003, pp. 6399-6404 and cover page.
International Preliminary Report on Patentability and Written Opinion issued Oct. 26, 2012 in PCT/JP2011/059480 filed Apr. 12, 2011.
Jaspreet Kaur, et al., "Differential roles played by the native cysteine residues of the yeast glutathione transporter, Hgt1p", FEMS Yeast Res, 9, 2009, pp. 849-866.
K. Mehdi, et al., "gamma-Glutamyl transpeptidase in the yeast Saccharomyces cerevisiae and its role in the vacuolar transport and metabolism of glutathione", Biochemical Journal, vol. 359, No. 3, Nov. 1, 2001, pp. 631-637.
K. Mehdi, et al., "γ-Glutamyl transpeptidase in the yeast Saccharomyces cerevisiae and its role in the vacuolar transport and metabolism of glutathione", Biochemical Journal, vol. 359, No. 3, Nov. 1, 2001, pp. 631-637.
K. Rambabu, et al., "Studies on the properties of the variants of gamma-glutamyl transpeptidase in human urine", J. Biosci., vol. 4, No. 3, Sep. 1, 1982, pp. 287-294.
Kuniki Kino, et al., "Novel substrate specificity of glutathione synthesis enzymes from Streptococcus agalactiae and Colstridium acetobutylicum", Biochemical and Biophysical Research Communications, 352, 2007, pp. 351-359.
Minghua Wang, et al., "Activation of Family C G-protein-coupled Receptors by the Tripeptide Glutathione", Joumal of Biological Chemistry, vol. 281, No. 13, Mar. 31, 2006, pp. 8864-8870.
Naoyuki Taniguchi, "gamma-glutamyl cycle", Protein Nucleic acid Enzyme, Special Issue "Epoch of Glutathione research", vol. 33, No. 9, pp. 1432-1441 plus cover page (with partial English-language translation).
Naoyuki Taniguchi, "γ-glutamyl cycle", Protein Nucleic acid Enzyme, Special Issue "Epoch of Glutathione research", vol. 33, No. 9, pp. 1432-1441 plus cover page (with partial English-language translation).
Nisbet, T. M. et al., J. Gen. Microbiol. 115: 127-133 (1979). *
Ronald A. Vitali, et al., "The Isolation of gamma-L-Glutamyl Peptides from a Fermentation Broth", The Journal of Biological Chemistry, vol. 240, No. 6, Jun. 1965, pp. 2508-2511.
Ronald A. Vitali, et al., "The Isolation of γ-L-Glutamyl Peptides from a Fermentation Broth", The Journal of Biological Chemistry, vol. 240, No. 6, Jun. 1965, pp. 2508-2511.
Simone Toelstede, et al., "Kokumi-Active Glutamyl Peptides in Cheeses and Their Biogeneration by Penicillium roquefortil", Journal of Agricultural and Food Chemistry, 57, 2009, pp. 3738-3748.
Takeaki Ohsu, et al., "Involvement of the Calcium-sensing Receptor in Human Taste Perception", Journal of Biological Chemistry, vol. 285, No. 2, Jan. 8, 2010, pp. 1016-1022.
U.S. Appl. No. 13/593,974, filed Aug. 24, 2012, Nishiuchi, et al.
U.S. Appl. No. 13/838,065, filed Mar. 15, 2013, Nishiuchi, et al.
Wen, S. et al. 2004. Utilization of amino acids to enhance glutathione production in Saccharomyces cerevisiae. Enzy. Microbial Technol. 35: 501-507. *
Wiles, A. M. et al. Microbiology, 152: 3133-3145 (2006). *
Yoichi Ueda, et al., "Characteristic Flavor Constituents in Water Extract of Garlic", Agric. Biol. Chem., 54(1), 1990, pp. 163-169.
Yoichi Ueda, et al., "Flavor Characteristics of Glutathione in Raw and Cooked Foodstuffs", Biosci. Biotech. Biochem., 61(12), 1997, pp. 1977-1980.

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* Cited by examiner, † Cited by third party
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US11925672B2 (en) 2018-08-08 2024-03-12 Sempio Foods Company Peptide having antioxidant activity and composition containing same

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